The Mashed Potato Casserole is a delicious yet super convenient way to make mashed potatoes ahead of time! A layer of cheese and bacon keeps the mashed potatoes from drying out as it warms in the oven, turning that humble side into something nastier and more decadent. Oh, the power of cheese (plus bacon)!
Freshly prepared or assembled in advance and reheated as needed. Serve in place of plain oil mash.
Make-ahead mashed potato
With the holidays fast approaching, I thought it was time to share my favorite way to make mashed potatoes ahead of time.
The problem with making mashed potatoes ahead of time is that you can’t just reheat it in the microwave or oven. You might think a little milk and a good mix will do the trick. But I can tell you, it’s the path to a mouth full of fudge horror.
While there are practical ways to successfully reheat cold mashed potatoes*, the Big Pan Creamy Mashed Potato Casserole won the award in the easiest and most convincing way I know!
It also won the Least Effort of the Day award because you literally put the pre-assembled dish in the oven. It’s a 10/10 win-win – nothing beats your holiday party menu! !
- How I reheat plain mashed potatoes: cold mashed potatoes in hot cream (recipe here, but be careful, more work for the day) or dipped in heavy piping bags in hot cream boiling water, tricks used by caterers (Check out my Instagram demo here).
Is there such a thing as too much bacon??
Confession: I feel like I’m a little clumsy with the bacon in the photo, and I’m a bit lacking in material for the recipe video! ! So written recipe cards are a happy medium.
But actually, if you look at the photo below, it looks tempting, almost covered in bacon. And… is there such a thing as too much bacon?
What you need for Mashed Potato Casserole
Here’s what you need to make Mashed Potato Casserole:
- Potato – Floury and all-rounder potatoes work best to achieve a fluffy yet creamy mash without fussing with potato ricers and other gadgets.
– Australia: the cheap dirt-brushed potatoes sold everywhere (called Sebago) are ideal
– US: Russet
– UK: Maris Piper
- Milk – Our liquid to loosen the potato up to form mash. If making ahead, we add extra (see How To Make section for more).
- Sour cream – I prefer using sour cream rather than cream in mashed potato casserole because the slight tang makes a nice counterpoint to all the other richness going on here (butter, cheese, bacon). It doesn’t make it sour in the least. It sort of adds creaminess into the mash without adding cloying richness. Does that makes sense??
- Butter – Mash without butter is not mash. #strongopinions!
- Cheese – I use a combination: Mozzarella for excellent melty-cheesy-stretchiness. Then Red Leicester for flavour (it’s savoury and a bit sharp, like aged cheddar), and to add a lovely orange hue to the mash surface. If you’re in the States, your orange cheddar is ideal here. Otherwise, use any melting cheese you like (colby and Monterey Jack are other personal favourites). If you opt to use mozzarella as your main cheese, add a handful of parmesan for flavour because mozzarella alone is actually quite bland and lacks saltiness.
Shred your own – One of my five non-negotiable rules stated loudly on the first page of my cookbook is, “Always shred your own cheese”! Store-bought pre-shredded cheese is coated in anti-caking agents which prevent it from melting as well as freshly-grated. I use a standard box grater for the work.
Pack your cups of cheese – For consistency I prefer weight over volume to measure cheese. So I’ll weigh a hunk of cheese before grating it. But if you are using cup measures, be sure to pack your cups tightly when measuring the shredded cheese otherwise you will be short. Nobody wants to be short on cheese, ever!
- Bacon – For sprinkling over the casserole surface. Note: I always use streaky bacon. Because fat = flavour! Also, fatty bacon crisps up and colours better, without drying out.
- Green onion – For a touch of oniony freshness and colour.
How to make Mashed Potato Casserole
No rocket science here. We make mashed potatoes, spread it on a baking sheet, top it with cheese, bacon, stop here if it’s quick. Finally, the day you make it, bake it!
- Cut potatoes – Peel and cut the potatoes into even sized pieces.
- Boil until soft – Place the potatoes in cold salted water. Bring it up to a boil over high heat then reduce the heat down to medium high or medium so it is simmering rapidly. Cook for 15 minutes (no lid) or until the potatoes are very soft. They should fall apart when you jab it with a fork.
- Mash – Drain the potatoes well in a colander and pour them back into the empty pot. Mash with the butter, milk, sour cream and salt. MAKE-AHEAD ADJUSTMENT – If you are making this dish with the intention of serving it the next day, then add an extra 2/3 cup milk. The mash will seem too loose, but this is intentional. It is to factor in the fact that mashed potato firms up when refrigerated overnight. So once reheated, it has the same consistency as when it is freshly made! Potato masher – I like to use a potato masher that is like a round disc with holes in it, as pictured above. It’s the fastest and most effective tool for a smooth mash without using a potato ricer (which I reserve just for Paris Mash, when seeking that next-level-luxe, ultra-smooth, 3-Michelin-restaurant result!).
- Spread in a casserole dish.
- Top with the cheeses and bacon. (Yes you eagle-eyed spotters, I was short on bacon for these shots )
For make ahead – At this stage, the assembled dish can be popped in the fridge for up to 3 days. Just take it out of the fridge 2 hours ahead so it has time to de-chill. This will make it reheat faster and more evenly in the oven.
- Cover with foil then bake for 20 minutes at 200°C / 400°F (180°C fan), if freshly made. Add an extra 15 minutes if you’re reheating a make-ahead casserole you prepared the day before.
- Uncover – Remove from the oven and bake for a further 10 minutes until bubbly and golden.
- Voila, ready to serve! Crack through that molten cheese surface and marvel at how creamy the mash underneath is!
How to serve Mashed Potato Casserole
This is a dish designed to be a side. (I know we can all picture it moonlighting as a standalone dish after a big night on the turps or a shocking day at work, but it’s meant to take the place of traditional plain mashed potato, I swear.) Because actually, though this has cheese and bacon on it, underneath is all creamy plain mashed potato.
So place it on the table or on the buffet alongside the mains and let everybody dig in and help themselves! Try to get in first though. Because you know full well the first in line are going to take more than their fair share of that cheese bacon topping – and we know full well we also cannot blame them